The present invention provides a lock assembly for a sliding panel-type window which is intended to be mounted on the rear-end of the sliding panel. The lock assembly includes a pivotally mounted lever with a bent-over extremity. The lever may be turned manually when the window is closed to cause the extremity to be received in a hole in the frame of the window. The lever serves to lock the window in a completely closed position, and in a series of partially open positions, and it also serves to prevent the panel from being lifted up and out of the track in which it slides.
It is usual in the prior art for sliding panel windows to be locked by means of a spring-loaded latch such as described, for example, in U.S. Pat. No. 3,881,759. However, even though such latches may serve to hold the windows locked against sliding motion, the sliding panels can still be removed from their frames by intruders, by moving the sliding panels upwardly and out of their tracks. The simple lock assembly of the present invention positively locks the window, and it also serves to prevent the sliding panel from being lifted up and out of its track.
Accordingly, a general objective of the present invention is to provide a dead bolt type of tamper-proof lock for a sliding panel window which serves to hold the sliding panel in its track and which restrains the panel from any vertical or horizontal movement, thereby to provide positive protection against illegal entry.
Another objective of the invention is to provide such a lock assembly which is easy to install, and one which may be mounted on virtually all existing horizontal or vertical sliding panel or doors.
Yet another objective of the invention is to provide such a lock assembly which is easy to operate between a position in which a sliding panel is free to move back and forth in its track and a position in which the panel is securely locked and restrained in its frame.
A feature of the lock assembly of the invention is that it may be installed not only to secure the sliding panel in a closed position, but also to secure the panel in one or more partially open positions for ventilation without loss of security.
Another feature of the lock assembly of the invention is that it is absolutely safe, and can be opened quickly and easily in case of fire or other emergency for rapid exit.